I need help on this question can anyone help?

Find a number such that if you add 8 and divide the result by 4 you will get the same answer as if you subtracted 3 from the original number and divided by 2

If the speed of an electromagnetic wave is 100,000 cm/s and its wavelength is 100 cm, what is its frequency? a) 100,000 cycles per second (hz) b) 1 × 10-3 cycles per second (hz) c) 10,000,000 cycles per second (hz) d) 1,000 cycles per second (hz)

How can the correlation in the scatter plot graph below best be described? positive correlation negative correlation both positive and negative no correlation