The diagram below shows one cycle of a circular function.
 

The amplitude and period of this function are respectively

1. `3\ \ text(and)\ \ 2 `
2. `3\ \ text(and)\ \ (pi)/(2)`
3. `4\ \ text(and)\ \ (pi)/(4)`
4. `3\ \ text(and)\ \ 4`

The graph shown could have equation

1. `y = 2cos(x + pi/6) + 1`
2. `y = 2cos4(x - pi/6) + 1`
3. `y = 4sin2(x - pi/12) - 1`
4. `y = 3cos(2x + pi/6) - 1`