Answer: 135 grams
Step-by-step explanation:

As we know that,

where,
= mass of ice = 100 g
= mass of aluminium cup =? g
= final temperature =

= temperature of ice =

= temperature of aluminium cup=

= specific heat of ice=

= specific heat of aluminium cup =

Now put all the given values in equation (1), we get
![[100* 2.03* (20-(-10))]=-[m_2* 0.902* (20-70)]](https://img.qammunity.org/2020/formulas/physics/college/3agelm4g9h8znaqczpf58z7u37dadk1dyf.png)

Therefore, the mass of the aluminium cup was 135 g.