Which of the following terms is the best described as the number of waves that pass a point in one second

Which of the following is not a part of a wave? question 2 options: a: frequency b: refraction c: wavelength d: amplitude (whoever answers correctly first gets brainiest! ) ~kayla

Question 11 of 13 (1 point) jump to question: a stairway, ladder, or ramp must be present in excavations in which of the following situations? a. all trenches must have access/egress b. the trench is more than 15 feet wide but only 1 ½ feet deep c. the trench is more than 4 feet deep and the devices must be within 25 feet of all workers

What is friction? how does it affect the motion of an object?