a$.$ The multiplier will be

$$

multiple choice $1$

smaller, the smaller the MPC and the smaller the MPS$.$

larger, the larger the MPC and the smaller the MPS$.$

smaller, the larger the MPC and the smaller the MPS$.$

larger, the smaller the MPC and the larger the MPS$.$

$$

b$.$The multiplier effect

$$

multiple choice $2$

intensifies the effect of a decrease, but not an increase, in spending.

intensifies the effect of a spending change, whether it is an increase or a decrease.

diminishes the effect of a spending change, whether it is an increase or a decrease.

intensifies the effect of an increase, but not a decrease, in spending.