Why do scientists believe the universe is still expanding? a. The further away an object is, the higher the temperature and pressure eventually become, causing nuclear fusion
b. Distant objects shift in frequency toward red on the electromagnetic spectrum, which tells us objects are moving away from us
c. Spiral galaxies spin, so they appear to be a rotating disk of stars and dust
d. Distant objects shift in frequency toward blue on the electromagnetic spectrum, which tells us objects are closer to us us

Isobars are lines of constant or equal pressure on a weather map. they can be used to find areas of low or high pressure over a broad area, and they can tell us how intense the system may be. on weather maps, you may have noticed areas that have a large l or h over a region with lines circling around them. the l stands for low pressure and h stands for high pressure. the lines circling them are isobars. check out the pressure system and isobars over georgia and florida. what is the present weather in this area ? a) clear and sunny b) cold and cloudy c) changing weather d) lots of precipitation