A scientist wants to measure the relationship between humidity in the summer and the number of home runs in baseball. Which of the following is a
testable question about this topic?
A. Are home runs more exciting during the summer?
O B. Should fans like the players who hit the most home runs?
O C. Are home runs more fun to watch than normal hits?
D. Are there more home runs during the more humid months of the
summer?

D

Explanation:

The most suitable testable question. in this case, would be that 'are there more home runs during the more humid months of the  summer?'

Since the aim of the investigation is to find the relationship between humidity and the number of home runs, measuring the number of home runs during the more humid months in the summer and comparing the data to the number of home runs during the less humid months in the same summer would provide the answer.

Only option D raises a valid question that is relevant to the aim of the investigation.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

there is no correct list among the choices you've provided.

the list might look something like this:

-- baby human

-- piccolo

-- flute

-- soprano singer

-- trumpet

-- tenor singer

-- trombone

-- baritone singer

-- baritone horn

-- bass singer

-- tuba

since i had to make up the list myself, i made it easy on myself, and i didn't try to shuffle the string instruments and woodwinds into it too.