The lowest note on a piano is 27,5 Hz. If strings with V = 84,7 m/s are used, how long should the piano string be?
(Unit = m)

Phase changes are chemical changes. true or false

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

Complete the statement about memory improvement. ( )involves organizing and breaking down information into easier groups to expand capacity. rehearsal is the verbal repetition of information. these techniques are especially important for the improvement of ( ) memory.