Balance this pls! _C7H9 + _HNO3 −−→ _C7H6(NO2 )3 + _H2O

a.3, 2, 1, 1
b. 1,1,3,3
c.2,1,1,3
d.1,3,1,1

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

What must occur for air masses to form fronts

Which of the following has wavelength longer than the wavelength of viable light? a) x rays b) gamma rays c) radios waves d) ultraviolet waves