Ablock of mass m = 2.0 kg slides head on into a spring of spring constant k = 260 n/m. when the block stops, it has compressed the spring by 14 cm. the coefficient of kinetic friction between block and floor is 0.42. while the block is in contact with the spring and being brought to rest, what are
(a) the work done by the spring force and
(b) the increase in thermal energy of the block-floor system?
(c) what is the block's speed just as the block reaches the spring? show all steps.

You have two photos of a person walking. one shows the person at the corner of third and main streets, the other shows the person at the corner of tenth and main streets. there are lampposts at every corner in this town, and the first picture shows it to be 10: 32: 00 exactly. the second picture shows it to be 10: 49: 30. you know three facts: (1) all of the clocks are synchronized; (2) there are exactly 12 equal-sized blocks per kilometer in this town; and (3) the streets that cross main in this area are numbered consecutively, with no interruptions. what is the person’s average speed in kilometers per hour?