Why did the tsar abdicate in march 1917?

there was a cute shortage of food and other comodiate in Russia.there was a seviuor faminin in the country. the prices shortup. The workers went on strike lawnesless preveiled every where the revolution started o 7th march every where the workers started the revolutionaries. stopped the jails.in present in many offices. because of these reasons Ts artist autocracy collapsed in 1917