Question

Scan the line from an Emily Dickinson poem. Label its metrical foot and its type of ending. The berry's cheek is plumper Ending

Answer 1

it is feminine because the syllables are not stressed 

Answer 2

The metrical foot of this line from Autumn by Emily Dickinson is the following:

The ber/ry's cheek/is plump/er (the bold letters represent the syllables stressed)

The ending is femenine because the line of the poem ends with an unaccented syllable.