A column form $15$ ft high is filled with $150$lb per cu ft concrete ata a temperature of $50$ degrees F$.$ the the concretr id type $1$ without the retarder. concrete will be placed with normal internal vibration to a depth of less than $4$ ft$.$ the rate of placement is $7$ ft per hour. calculate the lb per sqft of maximum pressure on the forms and draw the associated image od distribution of concrete pressure, labeling the height at which the maximum pressure will occur.