What are the two forces acting on a balanced hot air balloon. of
O a. Gravity and Weight
O b.
Air resistance and upthrust
O c. Applied force and upthrust
d.
Gravity and air resistance

I want to say option C) Applied force and upthrust.

Explanation:

Sorry if my answer is wrong. You can look in your book or study up on the website.

b.

explanation:

the minimum constant speed at which she can catch the train is 2.7 m/s

given:

acceleration = 0.6

time = 4.5 s

to find:

velocity = ?

formula used:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

solution:

from 1st kinematic equation we get,

v = u + at

u = initial speed of train = 0 m/s

v = final speed of the train

a = acceleration of the train

t = time

v = 0 + (0.6 × 4.5)

v = 2.7 m/s

the minimum constant speed at which she can catch the train is 2.7 m/s