Pls help worth brain;liest just snawer the ones that are blank

A2k pendulum has a speed of 1 m/s at a height of 1/2 meter

Light from a sodium lamp passes through a diffraction grating that has 1000 slits per millimeter. the interference pattern is viewed on a screen 1.000 m behind the grating. the first (m = 1) two bright yellow fringes that are visible are 0.7288 m and 0.7300 m from the central maximum. what are the wavelengths of these two fringes?

A1000-kg car is moving at 30 m/s around a horizontal unbanked curve whose diameter is 0.20 km. what is the magnitude of the friction force required to keep the car from sliding?