Which of the following limits are of the form {{CMD_12}}? {{CMD_13}} {{CMD_14}}{{MATH_15}}{{CMD_16}} {{CMD_17}}{{MATH_18}}{{CMD_19}} {{CMD_20}}{{MATH_21}}{{CMD_22}} {{CMD_23}}{{MATH_24}}{{CMD_25}} {{CMD_26}}{{MATH_27}}{{CMD_28}} {{CMD_29}} {{CMD_30}}