Export a group in Figma to PNG at specific size?

Question

I have a group in Figma that is 1200 x 1200 pixels. I need to export it as a PNG at the following sizes: 16x16, 32x32, 48x48, 128x128.

Can I do this without having to resize the group? It's annoying to have to create multiple sizes and there's a border radius set in pixels which doenst scale correctly.

UPDATE: I Looked under export settings but I don't see the option I need there:

Answer 1

1. Select the group

2. In the Export panel, click the + icon to add an export option

Then proceed as per the screenshot below, repeat step 2 for as many sizes as required.

Note: "w" means width in pixels, or you can use "h" for height in pixels.