Which of the following statements about biofuels is true? a. biofuels are composed of 100% renewable materials. b. algae is the leading source of biofuels. c. energy processing from corn biofuels is not energy efficient. d. corn is the only source of biofuels.

An engine undergoes a cycle as shown in the diagram. during a complete cycle the work done by the gas is 28.5×103 j and the energy transferred thermally out is 99.4×103 j. there are 1.5×1024 gas molecules and they have three active degrees of freedom. 6. (6 pts) during which process(es) is energy transferred thermally into the gas? a. 1→2 b. 2→3 c. 4→1 d. 1→2 and 4→1 e. none of the above

Acertain radio station broadcasts radio waves that have a wavelength of 298cm what is its broadcast frequency?

Ablock of mass m slides on a horizontal frictionless table with an initial speed v0 . it then compresses a spring of force constant k and is brought to rest. the acceleration of gravity is 9.8 m/s2 . how much is the spring compressed x from its natural length?