Đưa phương trình sau về dạng chính tắc:
(∂^2 z)/〖∂x〗^2 +2 (∂^2 z)/∂x∂y+(∂^2 z)/〖∂y〗^2 =0

Joe owns a fast-food restaurant and wants to know the average time it takes for customers to receive their orders. his restaurant serves about 500 customers a day. he timed 5 orders, and the order times he collected, given in minutes, are shown below. can the approximate order fulfillment time for all of the restaurant's customers be calculated from the given data? if so, calculate it. non-integer answers should be rounded to the nearest tenth. if no assumption can be made, type "0" in the box. the approximate order fulfillment time for all of the restaurant's customers is minutes.

Azookeeper predicted the weight of a new baby elephant to be 233 pounds when it was born. the elephant actually weighed 265 pounds at birth. what was the percent error of the zookeeper's prediction? asap

Kite abcd is rotated 180 degrees clockwise about the origin and then reflected over the y-axis, followed by a reflection over the x-axis. what is the location of point a after the transformations are complete?