<u>Answer:</u>
The acceleration of the plane and the time required to reach this speed is (a)= 7.5
and time(t) = 20 seconds
<u>Explanation:
</u>
Given data Initial velocity
= 0
Final velocity (
) = 150 m/second
Distance (d) = 1500 m
We have the formula, 
which gives
= 0+2a(1500)
22500 = 3000 a
acceleration (a) = 7.5 

150 = 7.5 t
t= 150/7.5 = 20
t = 20 seconds.
You test it over and over again. so basically you experiment on it more.
Hope this helps!
Ultraviolet rays from the sun are very strong, therefore if direct contact is made with skin, it could cause sun burn, or in a worser case skin cancer
Answer
given,
position of particle
x(t)= A t + B t²
A = -3.5 m/s
B = 3.9 m/s²
t = 3 s
a) x(t)= -3.5 t + 3.9 t²
velocity of the particle is equal to the differentiation of position w.r.t. time.

------(1)
velocity of the particle at t = 3 s
v = -3.5 + 7.8 x 3
v = 19.9 m/s
b) velocity of the particle at origin
time at which particle is at origin
x(t)= -3.5 t + 3.9 t²
0 = t (-3.5 + 3.9 t )
t = 0, 
t = 0 , 0.897 s
speed of the particle at t = 0.897 s
from equation (1)
v = -3.9 + 7.8 t
v = -3.9 + 7.8 x 0.897
v = 3.1 m/s
The answer is ”D”, “a higher frequency and a shorter wavelength.