Answer:
Orbital period, T = 1.00074 years
Explanation:
It is given that,
Orbital radius of a solar system planet, 
The orbital period of the planet can be calculated using third law of Kepler's. It is as follows :

M is the mass of the sun

T = 31559467.6761 s
T = 1.00074 years
So, a solar-system planet that has an orbital radius of 4 AU would have an orbital period of about 1.00074 years.
I think you want 2x10^-2
It’s called Scientific Notation
Answer:
Initial speed = 20 m/s
Final speed = 35 m/s
Time to speed up = 5 seconds
Explanation:
Directly from the information given:
Initial speed = 20 m/s
Final speed = 35 m/s
Time to speed up = 5 seconds