Notes

1a) A: Flower
B: Leaf

b) The roots absorb water and nutrients from the soil.
c) to attract insects.

2a) Draw a label line from the word "liver" to the upper right side of the diagram, above the stomach.
b) Draw a label line from the words "small intestine" to the lower right side of the diagram, below the stomach.

3a) Coal
Oil
Natural gas

b)Burning fossil fuels releases carbon dioxide and other pollutants, contributing to air pollution and climate change.
c) Biomass refers to organic materials, such as wood or agricultural residues, that can be used as a source of fuel.
d) Renewable means that a resource can be replenished naturally over time, ensuring its availability for the long term.
e) Deforestation occurs, leading to the loss of biodiversity, disruption of ecosystems, and potential negative impacts on climate regulation.


4. A: Non-metal (yellow powder with a low melting point)
B: Metal (pink solid which conducts heat)
C: Metal (hard, grey magnetic solid)
D: Metal (silver-colored liquid at room temperature which conducts electricity)
E: Non-metal (orange liquid which does not conduct electricity)
F: Non-metal (colorless gas)

5a) On the picture, draw an arrow to show the direction of the force of friction on the pencil case.
b) Angle of the ramp or slope: Ensure that the angle of the ramp remains constant for each test.
Surface of the ramp: Use the same type of material for the ramp surface to maintain consistency.
c) There might be a discrepancy or anomaly in the second time compared to the other trials, suggesting a potential error or inconsistency.
d) She could repeat the test for the pencil case and specifically focus on the second trial to see if the timing issue persists.

6a)
b)

7. object | energy from | energy to
---------------------|-------------|--------------
car | chemical | kinetic
light bulb | electrical | light
wood-burning fire | chemical | heat
battery in a circuit | chemical | electrical

8a) Rena may find it difficult to record the height of the bounce accurately due to the quick and dynamic nature of the tennis ball's rebound, making it challenging to precisely capture the maximum height.
b)
c) One advantage of plotting a graph is that trends can be seen more clearly than in a table.
d) If another group's points were far from their line on the graph, it suggests that their data points might be more variable or inconsistent.

9a) Layer A: Outer Core
Layer B: Inner Core

b) The inner core is a solid and it is made of iron and nickel.

10a) The rope does not move because the forces applied by Andy and James are equal and in opposite directions, resulting in a balanced force.
b) The pulling force from James must have decreased or stopped for the rope to start moving towards Andy. The net force now favors Andy's direction, causing the movement.

11a) 1. Plants in tray A appear healthier or have more growth.
2. Plants in tray B seem weaker or have less growth.

b) - Light is a form of energy.
- The Sun is a light source.

c) pH 7

12a) The part of this belief that is still accepted today is that the Earth is part of the solar system, and objects like the Moon go around the Earth.
b) People observed the apparent motion of celestial bodies in the sky, where the Sun, Moon, planets, and stars appeared to move across the celestial sphere, rising in the east and setting in the west. This observation led them to conclude that all these objects were orbiting around the Earth.

13a) draw arrows pointing towards the center of the Earth from each of the objects A, B, C, and D.
b) The mass of object A will be the same when placed on the Moon.
The weight of object A will be less when placed on the Moon.

14a) Indicator A turns red with aluminium sulfate.
Indicator B turns red with aluminium sulfate.
Indicator C becomes colorless with aluminium sulfate.

b) The red color in indicators A and B typically indicates acidity, while the colorless result in indicator C suggests neutrality. Therefore, the pH value for aluminium sulfate solution is likely to be acidic.

c) Indicator C becoming colorless indicates a neutral solution, but in the context of water treatment, aluminium sulfate is used to lower the pH of water by adding acidity.

15a)