This is the code that is being used. The error message is above.
library(deSolve)
y0 <- 0
parms <- c(c_0, k_a, k_c)
c_0 <- 175
k_a <- 0.16
k_c <-0.605
times <- seq(0, 24, 0.15)
blood_rate_solution <- lsoda(y = y0, times = times,
fun = calculate_blood_rate, parms=parms)