A student is observing standing waves. Changing the frequency of oscillation of a vertical string produces various harmonics. She changed the frequency from 30Hz to 60Hz. Which of the following must change as a result of this adjustment? Mark all that apply. a
The velocity must double
b
The wavelength must double
c
The velocity will remain the same
d
The wavelength must half
e
The velocity must half
f
The wavelength will remain the same

car a and b are moving in opposite directions

plz mark.me the brainliest i rlly need this kind of yours in exchange

f=ma newton's second law 7x8=56n

igneous rocks also form where plates converge. the subducting plate melts as it sinks into the crust of the earth, and the melt rises into the overriding plate forming volcanoes. metamorphic rocks are formed mainly in the lithosphere, wherever there is high pressure and high temperature. -woods