Explanation:
average speed = total distance travelled / total time travelled
time to travel the first 6km: 6 / 50 = 3/25 (h)
time to travel the next 6km: 6 / 90 = 1/15 (h)
[I think there's problem in the question 'cause 900km/h sounds impossible for normal person to travel in normal condition]
The total time: 3/25 + 1/15 = 14/75 (h)
Average speed over the 12 km drive will be:

A. Conduct an exam. Thomas might have a drug dependence.
(Please mark Brainliest! :D)
Answer:
A. 10 N
Explanation:
weight of melon is 1×10=10N..........
Answer:
(a) The work done is 0.05 J
(b) The force will stretch the spring by 3.8 cm
Explanation:
Given;
work done in stretching the spring from 30 cm to 45 cm, W = 3 J
extension of the spring, x = 45 cm - 30 cm = 15 cm = 0.15 m
The work done is given by;
W = ¹/₂kx²
where;
k is the force constant of the spring
k = 2W / x²
k = (2 x 3) / (0.15)²
k = 266.67 N/m
(a) the extension of the spring, x = 37 cm - 35 cm = 2 cm = 0.02 m
work done is given by;
W = ¹/₂kx²
W = ¹/₂ (266.67)(0.02)²
W = 0.05 J
(b) force = 10 N
natural length L = 30 cm
F = kx
x = F / k
x = 10 / 266.67
x = 0.0375 m
x = 3.75 cm = 3.8 cm
Thus a force of 10 N will stretch the spring by 3.8 cm