Which of the following has the largest R-value? (Use the table of R-values on page 111 of the textbook.)
A. 25 mm of air space with a reflective surface on the inside of the wall cavity
B. 50 mm of expanded polystyrene
C. 25 mm of fibreglass
D. 25 mm of rigid urethane foam

Will give brainliest! jay rides his 2.0-kg skateboard. he is moving at speed 5.8 m/s when he pushes off the board and continues to move forward in the air at 5.4 m/s. the board now goes forward at 13 m/s.a. determine jay’s mass.b. determine the change in the internal energy of the system during this process.(express your answer to two significant figures and include the appropriate units.)

Anybody wanna ? (picture included? )

The seven sisters, seven stars located more than 400 light-years away in the taurus constellation can be seen here with venus and another constellation, orion. the seven stars stay grouped together but seem to move, like the planet venus. why do stars seem to move like planets in the night sky?