R coding

Hi! Can you help me code this in R please?

Q5. Using d3, create the following variables and print first 8 rows for Netflix and the new columns along with conm and datadate:

1. Return on assets (roa) = oibdp / at

2. Free cash flow (fcf) = oancf / che

3. Strategic emphasis (strat_emph) = (adv - xrd) / at

My initial code is:

d2 = read.csv("tech_financials.csv", header=TRUE)

d3 <- filter(d1, sale > 0)

Thank you!