It's going to be the first one which is "A" for true
The sandstone is older.in order for the granite to have been formed with sandstone in its precnese then it had to have already exsisted in that area..making it older.
Scientific methods are used to study living things or investigate questions and solve problems.
Hey there!:
β-decay:
Unstable nucleus undergo β-decay in which a neutron is converted into proton , so
¹₀ n ----> ₁¹p + ₋₁⁰e ( Z + 1 )
The complete reaction is as follows:
²²⁷₈₉AC -----> ²²⁷₉₀ Th + ₋₁⁰e
Therefore , the daughter nucleus is : ²²⁷₉₀ Th
Hope that helps!