Answer:
8) 1500 feet
9) 20 miles
10) 4 Days
11) 2250 miles
12) 1 hour and 5 minutes
13) 27.27miles per hour
Explanation
8) There are 60 seconds in one minute so 60x25=1500 feet
9) 30 minutes is half of an hour so 40 miles ÷ 2 = 20 miles
10) 12x4=48
11) 500 miles x 4.5 hours is 2250 miles
12) Train leaves at 3pm after 60 miles it will be 4 pm and after 5 more miles 4:05 pm so 1 hour and 5 minutes
13)
Elmo = 40 minutes and 5 miles
Bert and Ernie = 45 minutes and 15 miles
Cookie Monster = 20 minutes and 10 miles
Home = 5 minutes abd 20 miles
Average Speed including stops is 27.27 miles per hour
To keep the energy going every day
Relative to the positive horizontal axis, rope 1 makes an angle of 90 + 20 = 110 degrees, while rope 2 makes an angle of 90 - 30 = 60 degrees.
By Newton's second law,
- the net horizontal force acting on the beam is
where 
are the magnitudes of the tensions in ropes 1 and 2, respectively;
- the net vertical force acting on the beam is
where 
and 
.
Eliminating 
, we have
Solve for .
Stars having less mass collapses early than those with more mass. This can be explained by Einstein's equation E=mc².
According to this equation, mass of stars is converted into light due to thermonuclear reactions occuring in the core of star which acts as engine of the stars. This thermonuclear reactions keeps star alive. Thermonuclear reactions occurs slowly in massive stars hence massive stars live more than light stars.
