During summer vacation, juan traveled a total distance of 400 miles. his trip took 8 hours.
what was the average speed during his trip?

What was the first instrument to ever record an earthquake?

How many neutrons does element x if it’s atomic number is 28 and its mass number is 87

The california mussel (mytilus californianus) attaches itself to a rock or other solid surface with a bundle of filaments known as the byssus. imagine that 15.0 j of work is done to stretch the distal end of the byssus. it releases 10.8 j of thermal energy as it relaxes. what is the resilience of the distal end of the byssus?