2/5 does not have the same value
12÷4=3 and 36÷12=3
so the ratio is same
therefore it is a geometry sequence


=108
I'm just estimating here,
5/48,3/16,0.5,0.75
A sinusoid is cyclical and has a period or frequency.
y = sin x is a sinusoid, with a period of 2π.
y = √x is not a sinusoid.
y = cos x is a sinusoid with a period of 2π.
Answer: y = √x is not a sinusoid.