Task:  Open the Khan Academy App, Select the Test Prep Tab, then select the Digital SAT Math Tab, review the materials and take the practice exam. 
Steps:
Open the Khan Academy App
Click on the Test prep Tab 
Click on the Digital SAT Math Tab
Swipe up to review the materials 
Swipe up to review the materials 
Swipe up to review the materials 
Swipe up to review the materials 
Swipe up to review the materials 
Swipe up to review the materials 
Click on the Take Course Challenge Button 
Click on the Let's go button to take a practice exam 
Select the option "B"
Click on the Check Button at the bottom right corner of the screen