Please help me don't wanna fail please help me please

If the slope of one line equals the slope of another line then ? a) the two lines are intersecting lines b) the two lines are perpendicular lines c) the two lines are parallel lines d) the two lines always have very steep slopes

In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.

Tan198=asin164=? how to solve this? ?