In November of $20$X$1,$ when you make your annual budget for the calendar year, you budget $$50$ per month for pet food for your dog in $20$X$2.$ Then on May $1,202$ you get a second dog $($who eats exactly as much as the first dog$),$ and on August $1,20$X$2$ the price of dog food increases by $10\%.($Round your answers to the nearest whole number. Refer to Chapter $5$ Sections $3-5.)$

a$.$ What is your actual annual cost of pet food for $202?$ $$1,050$

b$.$ How much is the variance for the cost of pet food for $202?$ $$425$

c$.$ What percentage of the variance is due to getting the second dog? $70\mathrm{.}83$

d$.$ What percentage of the variance is due to the increase in price? $10\%$