(a) If the rocket sled shown in Figure 4.31 starts with only one rocket burning, what is the magnitude of its
acceleration? Assume that the mass of the system is 2100
kg, the thrust T is 2.4 x 104 N, and the force of friction
opposing the motion is known to be 650 N. (b) Why is the
acceleration not one-fourth of what it is with all rockets
burning?

here are some information of the future of geothermal energy:

-the future of geothermal energy can pretty much be summed up with a single word: more

-scientists plan in going deeper than 120 meters

-we are hoping that one day, we will get all of our energy from renewable energy sources such as geothermal energy

hope this !

t = 1/400 h   ⇔ 0.0025 h ⇔ 9s ⇔ 0.15 m

any of the answers are correct.