Answer:
Mass and height
Explanation:
Gravitational potential energy is energy an object possesses because of its position in a gravitational field. The most common use of gravitational potential energy is for an object near the surface of the Earth where the gravitational acceleration can be assumed to be constant at about 
Which is represented as;

stands for gravitational potantial energy,
m stands for mass of object,
g is the gravitational constant and
h is the height.
Here we see that mass of object and height is directly proportional to the gravitational potential energy.
That means increasing in mass and height will result in increasing gravitational potential energy.
Answer:
The speed of the riders on the Singapore Flyer is approximately 0.262 m/s
Explanation:
The dimensions of the tallest Ferris wheel in the world are;
The diameter of the Ferris wheel, D = 150 m
The tine it takes the Ferris wheel to make a full circle, T = 30 minutes = 30 min × 60 s/min = 1,800 seconds
The angular velocity of the Ferris wheel, ω = 2·π/T
The linear velocity of the Ferris wheel, v = r·ω = The speed of the riders
Where;
r = The radius of the Ferris wheel = D/2
D = 150 m
∴ r = 150 m/2 = 75 m
∴ v = r·2·π/T
∴ v = 75 m × 2 × π/(1,800 s) ≈ 0.262 m/s
The speed of the riders on the Singapore Flyer, v ≈ 0.262 m/s
The correct answer is (a.) Hydra. Hydra is not a dwarf planet, instead, it is the moon of the dwarf planet, Pluto. There are only four accepted dwarf planets by the International Astronomical Union which were the Haumea, Pluto, Eris, and Makemake.