For z ∈ ℂ \{0}, let \(\rm f(z)=\frac{1}{z}\sin \left(\frac{1}{z}\right)\) and g(z) = f(z)sin (z). Which of the following statements are true?
1
f has an essential singularity at 0
2
g has an essential singularity at 0
3
f has a removable singularity at 0
4
g has a removable singularity at 0