This week ls1 has been learning mass.Here is my work https://docs.google.com/document/d/e/2PACX-1vT4Y1N7a6z2qRADNKk-PlmePBY7grJxjWLiX0MOGoKnSDkVNrZNQstsR0XDPZYCT7kh8Go8MQ4q9g8Z/pub.