C + 9 because you are adding o mode cars and an expression doesn't have an equal sign (=)
I am going to simplify the top before simplifying the rest.
tan = sin/cos, so tan * cos simplifies down to sin in the numerator. which leaves sin/sin which equals 1.
to make a long story short the answer is 1
If you reverse the first two letters
Na
Fe
Hg
Sn
They are actually symbols for elements
Na - Sodium
Fe - Iron
Hg - Mercury
Sn - Tin
Since Sn is a symbol for Tin and each pair of letters imply the starting letter of the element they are symbolizing, the answer is
1) T<span />
